how will people adapt change from FIAT CURRENCY to DIGITAL CURRENCY like BITCOIN?

The transition of fiat to crypto was already begun on the very early age of bitcoin. But the problem only of this is the acceptance of the government, nothing else because as we can see they are the only one that really do not like bitcoin.
But we can say the transition of fiat to bitcoin is can really help ones life.
When we do talk about transition then its general that if bitcoin become mainstream then we are already residing local fiat and make bitcoin is on the spot but we do know that these things are not possible. There might be a possible transition but only for those e-currency which is centralized or being made by government which I do see the high chance or possibility to happen than on talking into bitcoin itself.